The Big Red (11-12, 3-3) opened the game with a 12-2 run. Dartmouth (6-14, 2-4) trimmed the deficit to 12-7, but a 3-pointer by Cressler sparked a 17-5 spurt.
Cornell stretched its lead to 24, 41-17, on Peck's layup with 2:15 left in the first half and led by at least 18 points after halftime.
The Big Red made 17 of 27 shots in the opening frame while Dartmouth made as many shots (7 of 28) as turnovers.
Tyler Melville's 12 points led the Big Green.
Maryland point guard Melo Trimble, considered a lock to leave the program before struggling in the second half last season, has withdrawn from the NBA draft and will return for his junior season.
Louisville's Chinanu Onuaku, who recently underwent a medical procedure to correct a heart rhythm issue detected during the combine, will keep his name in the NBA draft pool.
Andrew White III will return to the Nebraska men's basketball team next season after removing his name from the NBA draft.